A cooling system includes a first cooling loop, a second cooling loop and a heat exchanger configured to transfer heat from the first cooling loop to the second cooling loop. The first cooling loop includes a vapor/liquid separation feature configured to separate vapor present in the first cooling loop due to a leak between the first cooling loop and the second cooling loop. The first cooling loop also includes a pressure sensor configured to detect an increase in pressure in the first cooling loop that may result from a leak of second coolant into the first cooling loop.

A cooling system includes a first cooling loop, a second cooling loop and a heat exchanger configured to transfer heat from the first cooling loop to the second cooling loop. The first cooling loop includes a vapor/liquid separation feature configured to separate vapor present in the first cooling loop due to a leak between the first cooling loop and the second cooling loop. The first cooling loop also includes a pressure sensor configured to detect an increase in pressure in the first cooling loop that may result from a leak of second coolant into the first cooling loop.

An air conditioner is provided that may include an outdoor unit having a compressor configured to compress a refrigerant; at least one indoor unit having an indoor heat exchanger, in which the refrigerant is heat exchanged, an indoor expansion valve that expands the refrigerant by adjusting an opening thereof, and a leak sensor that senses leakage of the refrigerant; a gaseous line that connects the outdoor unit and the at least one indoor unit and through which gaseous refrigerant flows; a liquid line that connects the outdoor unit and the at least one indoor unit and through which liquid refrigerant flows; a first shut-off valve disposed adjacent to the at least one indoor unit that opens and closes the gaseous line; a second shut-off valve disposed adjacent to the at least one indoor unit that opens and closes the liquid line; a supercooling pipe branched from the liquid line and connected to an inlet of the compressor; a supercooling expansion valve that expands refrigerant, flowing through the supercooling pipe, by adjusting an opening thereof; and a controller configured to control operation of the compressor and to control opening and closing of the first shut-off valve, the second shut-off valve, the indoor expansion valve, and the supercooling expansion valve. When the leak sensor senses the leakage of the refrigerant, the controller closes the first shut-off valve and the second shut-off valve.

A refrigeration cycle apparatus includes a refrigeration cycle circuit, a liquid receiver, a first valve and a second valve. The refrigeration cycle circuit includes a compressor, an outdoor heat exchanger and an indoor heat exchanger. The liquid receiver is provided in a second section located in the refrigeration cycle circuit. The second section is a section extending between the outdoor heat exchanger and the indoor heat exchanger without extending through the compressor. The first valve is provided in a first section in the refrigeration cycle circuit, and is a solenoid valve or a motor valve. The first section is a section extending between the outdoor heat exchanger and the indoor heat exchanger through the compressor. The second valve is provided in the second section and between the liquid receiver and the indoor heat exchanger, and is an electronic expansion valve, a solenoid valve or a motor valve.

A propane gas-utilizing system includes a housing having propane gas and a propane leakage prevention material having a catalyst, scavenger, and/or oxidizer of the propane gas arranged in the housing and including at least one of (a) an oxide material having at least one composition of formula (I): Ru.sub.1-xM.sub.xO.sub.2 (I), where 0<x≤0.1 and M is Ag, K, Pt, Rh, or Ir, or (b) an oxide material having at least one composition of formula (II): Co.sub.3-xM.sub.xO.sub.4 (II), where 0<x≤0.3, and M is Pd, Cu, or Sr, or (c) an oxide material having at least one composition of formula (III): MM′.sub.xO.sub.y (III), where x is a stoichiometric ratio of M′ to M, 0≤x≤1.5, y is a stoichiometric ratio of O to M, 1≤y≤3, M is an alkali metal, and M′ (if x>0) is Y, Ce, Nb, Ta, La, Nd, Mn, Ag, Au, or Cr.

A refrigerant leak detection and mitigation system/method for use in heating, ventilation, and air conditioning (HVAC) systems that incorporates a refrigerant gas sensor (RGS), sensor signal conditioner (SSC), alarm status indicator (ASI), and digital control processor (DCP) is disclosed. The RGS detects ambient refrigerant gas (ARG) and indicates this as a refrigerant sensor voltage (RSV) to the SSC. The DCP and SSC form a closed control loop (CCL) in which the SSC electrical characteristics are adjusted by the DCP such that the RSV is continuously and dynamically recalibrated to account for background refrigerant gas levels, changes in ambient air conditions, RGS manufacturing tolerances, and other field-specific operational conditions that impact the RGS detection capabilities. The DCP is configured to log alarms to the ASI if a RGS refrigerant leak is detected and optionally shutdown one or more HVAC system components such as a specific air handler leaking refrigerant.

An air-conditioning apparatus includes a refrigeration circuit, a first shut-off device provided at a pipe connecting a heat-source-side heat exchanger and an expansion device, a refrigerant leak detection device, and a controller. The controller controls a flow switching device to switch a connection state between a first connection state in which a discharge side of a compressor is connected to the heat-source-side heat exchanger, and a second connection state in which a suction side of the compressor is connected to the heat-source-side heat exchanger via an accumulator. When a refrigerant leak is detected, the controller performs a refrigerant retrieval operation and a refrigerant transfer operation.

A refrigerant leak detection and mitigation system/method for use in heating, ventilation, and air conditioning (HVAC) systems that incorporates a refrigerant gas sensor (RGS), sensor signal conditioner (SSC), alarm status indicator (ASI), and digital control processor (DCP) is disclosed. The RGS detects ambient refrigerant gas (ARG) and indicates this as a refrigerant sensor voltage (RSV) to the SSC. The DCP and SSC form a closed control loop (CCL) in which the SSC electrical characteristics are adjusted by the DCP such that the RSV is continuously and dynamically recalibrated to account for background refrigerant gas levels, changes in ambient air conditions, RGS manufacturing tolerances, and other field-specific operational conditions that impact the RGS detection capabilities. The DCP is configured to log alarms to the ASI if a RGS refrigerant leak is detected and optionally shutdown one or more HVAC system components such as a specific air handler leaking refrigerant.

The present invention relates to a gas heat pump system. A gas heat pump system according to one embodiment of the present invention comprises: a compressor for compressing a refrigerant; a gas engine for driving the compressor; a mixer for mixing air and fuel to generate a mixed gas to be supplied to the gas engine; a mixed gas supply line connected between the mixer and the gas engine; and a supercharger for supercharging the mixed gas supplied to the gas engine through the mixed gas supply line, wherein the supercharger comprises a sealed housing formed by sealing the remaining parts thereof other than an inlet port and an outlet port through which the mixed gas moves into and out of the housing, and a bypass line is provided between the sealed housing and the inlet port of the supercharger so as to resupply a mixed gas in the sealed housing to the inlet port of the supercharger. Therefore, the system can prevent a safety-related accident resulting from the leakage of the mixed gas out of the supplier and can reduce the amount of fuel consumption.

A refrigeration cycle apparatus includes a compressor, a four-way valve, a first outdoor heat exchanger, a first expansion valve, and an indoor heat exchanger. The four-way valve includes a casing, a first flow channel, a second flow channel, a flow channel switching piston, and a wall portion. The flow channel switching piston is configured to slide along an inner surface to switch between passing the refrigerant through the first flow channel and passing the refrigerant through the second flow channel. The wall portion is configured to slide along the inner surface together with the flow channel switching piston and is disposed with a space between the flow channel switching piston and wall portion to cover the flow channel switching piston.